73-year-old Motiur Rahman Nizami is a former legislator and minister under former prime minister Khaleda Zia

The Supreme Court of Bangladesh has cleared the final legal hurdle before the hanging of a top Islamist leader for his role in the violence and massacre during the country's 1971 war of independence against Pakistan.

The apex court on Thursday rejected a final appeal by Jamaat-e-Islami leader Motiur Rahman Nizami, clearing the latest in a series of high-profile executions of Islamist leaders held responsible for the 1971 violence.

In January the court had upheld the death penalty handed to him by the war crimes tribunal for crimes including genocide, rape and orchestration of the massacre of civilians and top intellectuals.

The 73-year-old Nizami is a former legislator and minister under former prime minister Khaleda Zia.

The Islamist party has criticised the conviction of its leaders for the 1971 violence, saying the move is politically motivated.

No Peace Without Justice, an organaisation campaigning against the war tribunal's convictions, said the proceedings area "a weapon of politically influenced revenge whose real aim is to target the political opposition", Reuters reported.

With the last-ditch legal move turned down by the top court, Nizami can now approach the president with a mercy plea. If the president rejects the appeal the former Al-Badr militia chief will be hanged.

Nizami is now held in the Kashimpur prison in Gazipur. Since 2013, Bangladesh has executed four opposition politicians including three Jamaat-e-Islami leaders.

The war crimes tribunal which was established in 2010, has convicted more than two dozen people for crimes against humanity and genocide.

The hardline Jamaat-e-Islami had supported the Pakistani military during the 1971 war in which East Pakistan broke away to form a new country called Bangladesh. Hundreds of thousands of people had died in the violence.